Undoubtedly this decade's most important book about medical negligence, A Measure of Malpractice provides a welcome antidote to the mythology and disinformation that has permeated most policy debate on the subject. This terse report, dense in data but not in style, summarizes in surprising detail the monumental work of the Harvard Medical Practice Study—distilling into one slender book the observations and analysis reported in fuller but more fragmentary form in various earlier publications. It should be required reading for every participant in the health care reform effort.